I've ordered from SB in the past with little or no problems. It was extra nice for me because I have smaller feet, which means that 1) retail stores usually don't carry my size and 2) with SB's policies, I could compare sizes and find a good fit between sizes 6 and 7, which can vary widely between manufacturers.
However, I recently ordered 6 pairs of shoes, with the intent of keeping 3 or 4 (if they fit). These were ECCO shoes and have Euro sizing. I wasn't sure about sizing, so I ordered a "true" size and one size up in both styles (along with different colors). I was sent an email to call their "processing department", afterwhich I was told that I would only be allowed to return up to 3 pairs of shoes -- regardless of whether they fit or not. I asked about their FREE shipping and no hassle return policies that they so proudly promote and the response was that they reserve the right to change the policies. I cancelled the order in disgust.
Yes, the shoes were a good price, around $140 each after a 20% discount. However, I refuse to be forced into accepting shoes that may not fit.
Shoebuy has lost a long-time customer. I will check out shoes.com or Zappos, as mentioned by previous posters.